Motor winding



0. E. ANDRUS MOTOR WINDING Jan. 29, 1952 2 SHEETS-SHEET 1 Filed Jan. 21,1948 INVENTOR. OrrinEAndrus BY ATTORNEY- Jan. 29, 1952 Q E, A R S2,583,804

MOTOR WINDING Filed Jan. 21, 1948 2 SHEETSSHEET 2 FIG. 3.

7 INVENTOR. Oz'rzn E.Anclrus ATTORNEY:

Patented Jan. 29, 1952 MOTOR WINDING Orrin E. Andrus, Altadena, Calii'.,assignor to A. 0. Smith Corporation, Milwaukee, Wis., a

corporation of New York Application January 21, 1948, Serial No. 3,387

2 Claims.

This invention relates to the construction of motor windings and thelike for submersion in various fluids.

Heretofore motor stator windings have been constructed with shortflexible leads for connection to a source of electricity.

In attempting to adapt such windings to operation while subjected tocorrosive and conductive fluids and the like it has been found necessaryto apply thereto one or more coatings of an impervious electricalinsulating varnish which is impregnated therein and baked at a suitabletemperature. When such a varnish is applied to the insulated flexiblelead wire and baked along with the varnish on the windings, the varnishcoating becomes brittle and prevents flexing of the lead wire. The heatof baking also injures the insulation for the lead wire. In the eventsuch a coated lead wire is bent the varnish cracks and also disrupts theinsulation on the wire, resulting in failure or breakdown of insulation.

The principal object of the present invention is to eliminate thedifliculty mentioned and to provide for flexible lead wires on windingsof the type referred to.

Another object of the invention is to provide fixed terminals on thewinding to which the stator terminal wires may be secured prior to theinsulation of the motor unit assembly with insulating varnish or thelike.

Another object is to provide an insulation seal for the lead wire.

A further object is to provide a terminal structure in which the windingconductor is relieved from any strain caused by the pull or flexing ofthe lead wire.

The invention is illustrated in the accompanying drawing in which:

Figure 1 is a perspective view of a stator winding showing the flexibleleads attached thereto;

Figure 2 is a similar enlarged detail view showing one of the leadterminals prior to attachment of the lead thereto;

Fig. is a fragmentary section taken longitudinally through a terminal ofFig. 1;

Fig. 4 is a fragmentary view, partly in section, of the stator terminalafter varnish impregnation; and

Fig. 5 is a section similar to Fig. 3 showing the terminal and flexiblelead prior to assembly.

The motor stator l composed of suitable metal laminations has the usualwinding protruding in a hollow cylindrical shape at each end to providethe end coils 2.

According to the invention one end of the stator has an anchor member 3composed of insulating material such as fabric reinforced Bakelite,which is secured to end coil 2 of the winding by tape 4.

The anchor member 3 is preferably in the form of a continuous ringhaving the same diameters as the inside and outside of the end coil 2 ofthe winding, although it may be constituted of a segment or segments.

Anchor member 3 has a plurality of fixed lead wire terminals 5 securedthereto, one for each stator terminal wire 6. Each terminal 5 comprisesa central binding post I of brass or other suitable conducting materialwith an inner head 8 fitting in a recess beneath the member 3 and towhich the stator terminal wire 6 is soldered or otherwise secured as at9. A suitable insulating sheet I0 is disposed over the wire 6 and coversthe head 8. The terminal wire 6 is additionally insulated from end coils2 before entry into binding post 1 by a sleeve ll of woven cotton or thelike. The wire 6 passes to the coil 2 through a suitable opening ininsulating sheet I.

The binding post 1 protrudes a substantial distance from the anchormember 3 and is threaded on its outer end to receive a securing nut l2.A sleeve ill of Bakelite or other insulating material is disposed uponthe binding post I and is held in place against anchor 3 by the nut 12.The sleeve I! may be of any length or may be entirely eliminated.

The drawings show three separate terminals 5 equally spaced around therim of the stator winding for a three phase alternating currentinduction motor. For other types of motors a different number ofterminals may be employed and they may be located differently.

The varnish coating ll extends substantially throughout the entirestator and its winding and over the sleeves [3 on the terminals andbonds the exposed portions of the stator together. A baking type varnishcoating I4 is preferably employed. The varnish secures the anchor 3,tape 4 and end coils 2 together and may be applied in one or morelayers. The terminals are therefore mounted rigidly upon the windingsand there is no flexing of any part that would crack the coating I4 andresult in insulation failure.

Each of the leads, which is adapted to connect to the terminals 5,comprises the usual conductor or lead wire cable IS with its insulation16, and a specially constructed metal cap I! with a tapped hole forthreading upon post 1. An outer sleeve I8 of highly insulating materialextends over the nut I2, sleeve l3 and the cable inasaasoi 3 mlation Itand cap". A lock washer I! is threaded on post I between nut l2 and thecap II to prevent loosening oi the latter from vibration.

The conductor cable 15 extends into and is secured as by soldering tothe shank of cap 11. The outer sleeve 18 preferably extends for thelength or the lead wire, as well as over the terminal 5.- A clamp 20encircles the sleeve It to secure it tightly upon the sleeve I! of theterminal and prevent entrance of liquid to the joint. 1

The sleeve I8 is preferably constructed of flexible insulating materialthat resists the liquids in which it is to be submerged. For thispurpose natural or synthetic rubber tubing or the like has been found tobe very satisfactory. Since the varnish is not applied to the cableinsulatlon IS, the lead wires may be flexed without fear of injurythereto as would be the case were it necessary to protect the lead byvarnish insulation.

In constructing the motor windings with flexible leads as described,after stator l is wound the end portion of the stator terminal wire 8that will be adjacent the conductors of end coils 2 is enclosed ininsulating sleeve II.

The wire 6 is then inserted through an opening in insulation in and intothe binding post 1, and is soldered at 9 to the post. Ring member 3 isapplied and slipped onto the several binding posts I with the heads 8 ofthe latter fitting into recesses in the back of the ring and withterminals 5 protruding.

The stator lead 6 is then twisted or folded down toward the statorwinding to bring the ring 3 in close position to the windings. The sheetI8 separates the ring from the conductors of the end coils to provide aneffective insulation therebetween and ring 3 is secured to the end coil2 by tape I.

The sleeve l3 and nut I! are then applied to secure the ring 3 in placeon the posts I.

The entire stator is then coated with the impervious electricallyinsulating resin or varnish l4 baked at the required temperature to makeit suitable for submerged operation. The varnish it completely coats allconductors to prevent electrolysis and shorting. The varnish is eitherprevented from coating the threads on the outer end of terminal 5 or isremoved following the impregnating and baking operation.

between. The tube It may be sealed onto insulation II by vulcanizationor by being cemented to cap member H.

The lead wires II and insulation tube II are readily replaceable withoutdamaging the windings or end coils of the motor.

Various embodiments of the invention may be employed within the scopeoi! the accompany- The lead wire [5 is secured to terminal 5 bythreading metal cap I'l oi. the lead I5 onto the end of the terminal 5.

The exposed terminal 5, nut l2 and lock washer [9 are sealed fromexposure to the surrounding fluid by the fluid tight sealing sleeve ortube l8 which is slipped over the terminal parts and sleeve alterassembly thereof around lead wire IS. The clamp 20 is assembled aroundtube l8 and tightened to seal tube l8 to sleeve l3 and prevent theentrance of surrounding fluid thereing claims.

I claim:

1. In an electric motor, or the like, adapted to have its statorsubmerged in an operating fluid, a winding for the stator, an anchormember disposed at an end of the winding and secured thereto, a bindingpost secured to said anchor member and having a tubular insulationelement extending from the anchor member over the body of the bindingpost for a substantial distance, and a continuous protective coatingsecured upon the winding and said insulation element, the outer end ofsaid post being exposed for connection to a lead wire and saidinsulating element providing a body for sealing with an insulatingmember on the lead wire.

2. In an electric motor, or the like, adapted to have its statorsubmerged in an operating fluid, a winding for the stator, an anchormember disposed at an end of the winding and secured there to, a bindingpost secured to said anchor member and having a tubular insulationelement extending from the anchor member over the body of the bindingpost for a substantial distance, and a continuous protective coatingsecured upon the winding and said insulation element, a flexible leadwire removably secured to the outer end of said post, an insulatingmember on said lead wire extending over the joint and over saidinsulation element, and means for sealing said insulating member to saidelement.

ORRIN E. ANDRUS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,153,580 Sheppy Sept. 14, 19151,261,193 Van Deventer Apr. 2, 1918 1,277,765 Smith Sept. 3, 19181,440,952 Apple Jan. 2, 1923 1,792,526 Apple Feb. 17, 1931 1,822,261Apple Sept. 8, 1931 1,925,892 Apple Sept. 5, 1933 2,206,672 PederquistJuly 2, 1940 2,280,855 Rose Apr. 28, 1942 2,286,952 Cannon et a1 June16, 1942 2,291,793 Chandler Aug. 4, 1942 2,435,231 Sigmund et a1. Feb.3, 1948 FOREIGN PATENTS Number Country Date 451,776 Great Britain Aug.11, 1936

